000 AXNT20 KNHC 150003 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT SUN JUN 14 2015 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS OF SOUTH AMERICA...AND ATLANTIC OCEAN TO THE AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2345 UTC. ...SPECIAL FEATURES... A SURFACE TROUGH OF LOW PRESSURE MOVED OFF OF THE YUCATAN PENINSULA TO THE SW GULF OF MEXICO IN THE AFTERNOON. AIRCRAFT RECON DATA DEPICT A BROAD LOW CENTER OF 1007 MB FORMED IN THE SOUTHERN TROUGH NEAR 22N91W. THE SYSTEM IS ACCOMPANIED BY AN AREA OF THUNDERSTORMS S OF 26N BETWEEN 84W AND 92W INCLUDING THE YUCATAN CHANNEL...AND GALE-FORCE WINDS WELL TO THE EAST OF THE TROUGH. THIS WEATHER SYSTEM IS EXPECTED TO MOVE NW OVER THE NEXT COUPLE OF DAYS ACROSS THE WESTERN GULF OF MEXICO WHERE UPPER LEVEL WINDS ARE FORECAST TO BECOME MORE FAVORABLE FOR TROPICAL CYCLONE FORMATION. ADDITIONAL INFORMATION ABOUT THIS FEATURE IS FOUND IN THE HIGH SEAS FORECAST UNDER WMO FZNT02 KNHC OR MIAHSFAT2. THE CHANCES OF THIS SYSTEM DEVELOPING INTO A TROPICAL CYCLONE DURING THE NEXT 48 HOURS IS HIGH. ...TROPICAL WAVES... A TROPICAL WAVE IS ON THE E TROPICAL ATLC WITH AXIS NEAR 17W MOVING W AT 5 KT. SSMI TPW IMAGERY INDICATES MODERATE MOISTURE ACCOMPANY THIS WAVE THAT IS BEING ENGULFED BY SAHARAN DRY AIR AND DUST. ISOLATED SCATTERED MODERATE CONVECTION IS FROM 03N TO 12N E OF 26W. A TROPICAL WAVE IS OVER THE WESTERN TROPICAL ATLANTIC WITH AXIS NEAR 43W MOVING W AT 15 KT OVER THE PAST 24 HOURS. SAHARAN DRY AIR AND DUST ARE IN THE WAVE ENVIRONMENT...THUS HINDERING CONVECTION. A TROPICAL WAVE IS ALONG 52W/53W MOVING W AT 15 KT OVER THE PAST 24 HOURS. SSMI TPW IMAGERY INDICATE AN INCREASE IN MOISTURE IN THE CENTRAL AND SOUTHERN WAVE ENVIRONMENT THAT SUPPORT SCATTERED MODERATE CONVECTION S OF 11N BETWEEN 50W AND 62W. SOME SAHARAN DRY AIR AND DUST ARE IN THE NORTHERN HALF OF THIS WAVE WHICH IS INHIBITING CONVECTIVE PRECIPITATION OVER THIS AREA. A TROPICAL WAVE IS OVER THE WESTERN CARIBBEAN WITH AXIS NEAR 79W MOVING W AT 15 KT OVER THE PAST 24 HOURS. SSMI TOTAL PRECIPITABLE WATER IMAGERY SHOW THIS WAVE IS EMBEDDED IN RELATIVELY DRY AIR...THUS RESULTING IN A LACK OF CONVECTION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 10N14W TO 08N16W. THE ITCZ BEGINS NEAR 07N20W AND CONTINUES THROUGH 06N40W...IT RESUMES NEAR 06N45W TO 07N52W. OTHER THAN CONVECTION DISCUSSED IN THE TROPICAL WAVES SECTION...ISOLATED MODERATE CONVECTION IS FROM 03N TO 05N BETWEEN 30W AND 39W. ...DISCUSSION... THE GULF OF MEXICO... AN UPPER LEVEL LOW IS CENTERED OVER THE SW GULF OF MEXICO SUPPORTING A SURFACE TROUGH OF LOW PRESSURE OFF OF THE YUCATAN PENINSULA WITH A LOW CENTER OF 1007 MB IN THE SOUTHERN TROUGH NEAR 22N91W. EAST OF THE UPPER LOW A DIFFLUENT ENVIRONMENT SUPPORT THUNDERSTORMS S OF 26N BETWEEN 84W AND 92W INCLUDING THE YUCATAN CHANNEL. GALE FORCE WINDS ARE OCCURRING OVER PORTIONS OF THE SOUTHEASTERN GULF ASSOCIATED WITH THIS FEATURE. SEE THE SPECIAL FEATURES SECTION ABOVE FOR MORE DETAILS. ISOLATED SHOWERS AND TSTMS ARE NOTED IN RADAR WITHIN 75 NM OFF THE WESTERN COAST OF FLORIDA. ASIDE FROM THE STRONGER WINDS NEAR THE SPECIAL FEATURE...SOUTHEASTERLY SURFACE WINDS OF 15 TO 20 KT DOMINATE THE BASIN. OVER THE NEXT COUPLE OF DAYS THE SPECIAL FEATURE WILL MOVE NORTHWESTWARD ACROSS THE WESTERN GULF OF MEXICO WHERE UPPER LEVEL WINDS ARE FORECAST TO BECOME MORE FAVORABLE FOR TROPICAL CYCLONE FORMATION. EXPECT NUMEROUS AREAS OF CONVECTION TO SPREAD ACROSS THE CENTRAL GULF TO NW GULF THROUGH MONDAY...ALONG WITH AREAS OF GALE FORCE WINDS. THE CARIBBEAN SEA... ABUNDANT LOW LEVEL MOISTURE ASSOCIATED WITH A SURFACE TROUGH OF LOW PRESSURE OFF OF THE YUCATAN PENINSULA ALONG WITH A DIFFLUENT ENVIRONMENT ALOFT ALONG THE YUCATAN CHANNEL SUPPORT SCATTERED MODERATE CONVECTION N OF 18N W OF 83W. ANOTHER AREA OF DIFFLUENCE IS ALONG CUBA BEING GENERATED BY AN ELONGATED UPPER RIDGE ACROSS THE EASTERN GULF OF MEXICO AND A TROUGH COVERING THE CENTRAL AND EASTERN CARIBBEAN. THIS ENVIRONMENT ALOFT COMBINED WITH MODERATE LOW LEVEL MOISTURE IS SUPPORTING SHOWERS AND TSTMS ACROSS THE ISLAND AND ADJACENT WATERS. THESE SHOWERS AND TSTMS EXTENDS TO HAITI AND SW DOMINICAN REPUBLIC. A TROPICAL WAVE IS OVER THE WESTERN CARIBBEAN. PLEASE SEE THE TROPICAL WAVES SECTION FOR MORE DETAILS. SAHARAN DRY AIR AND DUST COVER PORTIONS OF THE CENTRAL AND EASTERN CARIBBEAN HINDERING CONVECTION. SE WINDS OF 20 TO 25 KT ARE N OF 18N W OF 85W ASSOCIATED WITH GALE FORCE WINDS NEAR THE YUCATAN PENINSULA. NE TO E WINDS OF 20 TO 25 KT ARE 11N TO 13N BETWEEN 67W AND 77W. OVER THE NEXT 24 HOURS CONVECTION AND WINDS WILL DECREASE OVER THE NORTHWESTERN CARIBBEAN AS THE SPECIAL FEATURE LIFTS NW ACROSS THE GULF OF MEXICO. A TROPICAL WAVE APPROACHING THE LESSER ANTILLES MAY BRING CONVECTION TO THE ISLANDS BY MONDAY NIGHT. ...HISPANIOLA... SAHARAN DUST IS BEING OBSERVED OVER THE EASTERN ISLAND TODAY IN ADDITION TO RELATIVELY DRY AIR IN THE LOW LEVELS. THESE FACTORS ARE HELPING TO INHIBIT SHOWER AND THUNDERSTORM ACTIVITY OVER THIS PORTION OF THE ISLAND. AN AREA OF DIFFLUENCE IS ALONG CUBA BEING GENERATED BY AN ELONGATED UPPER RIDGE ACROSS THE EASTERN GULF OF MEXICO AND A TROUGH COVERING THE CENTRAL AND EASTERN CARIBBEAN. THIS ENVIRONMENT ALOFT COMBINED WITH MODERATE LOW LEVEL MOISTURE IS SUPPORTING SHOWERS AND TSTMS OVER HAITI AND SW DOMINICAN REPUBLIC. THE ATLANTIC OCEAN... A WEAK 1021 MB HIGH IS CENTERED NEAR 29N79W. UPPER LEVEL RIDGING JUST S OF THIS SURFACE HIGH IS PRODUCING DIFFLUENT ENVIRONMENT THAT ALONG MODERATE LOW LEVEL MOISTURE SUPPORT ISOLATED SHOWERS AND TSTMS S OF 26N W OF 60W. SURFACE HIGH PRESSURE AND RIDGING DOMINATES ELSEWHERE ACROSS THE ATLC WATERS WITH FAIR WEATHER AND IS EXPECTED TO BE THE MAIN FEATURE DURING THE NEXT THREE DAYS. FOR TROPICAL WAVES INFORMATION SEE THE SECTION ABOVE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR